U4030B Datasheet | TEMIC Semiconductors

Description The U4030B is an electronic speech circuit for standard and feature telephones. It replaces the hybrid transformer, earphone and microphone interface and the supply voltage generation for external ponents, e.g. dialer or microputers. Using the U4030B in telephone circuit designs can improve transmission quality and results in cost savings through shorter and more flexible design procedures. It reduces the amount of external ponents needed. The U4030B uses TEMIC’s reliable bipolar technology and is offered in a SO20 package. Features D Microphone amplifier with - Symmetrical input - Privacy function - Anticlipping D Built in ear protection D Power down input D Mute input D DTMF interface D Low line impedance during pulse dialing Benefits D Independent adjustment of - Transmission gain - Receiving gain - Sidetone suppression - Frequency response D Low-impedance supply voltage for all external blocks D Supply voltage for an electret microphone Applications D Standard telephone D Fax machine D Answering machine D Cordless telephone Block Diagram GT 11 DTMF PRIV MIC1 MIC2 10 - + MICO 9 ST 5 + - GR 6 - + Ear protection RECO 7 16 12 13 4 TXA REC.ATT. 15 Limiter Mute 3 CLIM 8 MUTE 17 PD Power supply U 4030 B 14 GND 18 SWAMP 1 VM 20 VD 19 2 VL RDC VC 93 7618 e Figure 1. Ordering Information Extended Type Number U4030B-AFL U4030B-AFLG3 Package SO20 SO20 Remarks Taped and reeled Rev. A2, 27-Jan-98 1 (14) Pin Description Pin 10 Function Input for DTMF signals (ACcoupled). In mute condition a small portion of the signal at this pin is monitored to the receive output GT Input for transmit gain control MIC1 Inverting input of microphone amplifier MIC2 Non-inverting input of microphone amplifier GND Ground (reference point for DC and AC signals) VL Line voltage PRIVACY Active high input to disable microphone amplifier PD Power down input. Active high input for reducing the current consumption of the circuit. Simultaneously VL is shorted by an...